Heat doesn't let up in knockout stage

The United States took part in the World Cup's first water break, and they needed it after their demanding travel schedule.

Finally something (else) new in football Yes, goal-line technology has arrived, but this World Cup has also brought another radical innovation. On June 22, the football world witnessed the first water break in a World Cup match, after 40 minutes of the fixture between Portugal and the United States that would eventually finish 2-2.

The 85 degree temperature in the Amazonia capital of Manaus, coupled with over 70 percent humidity, determined that "feels like" temperature (or, more technically, Wet Bulb Globe Temperature Index) surpassed 89.6 degrees, and therefore a two-minute pause -- stretched to three by players and referee -- became mandatory.

Informal breaks had happened in previous matches, such as the Russia-South Korea game in the extremely hot Cuiaba, but only in Manaus conditions surpassed the aforementioned threshold during the group stage of this World Cup.

Defeating the weather and travel handicap...

In these first two weeks, tough weather and extensive travel have impacted quite diversely various teams. For those who suffered and managed to overcome them, its toll could appear during what remains of the tournament in the shape of tired legs.

For instance, the U.S have traveled over 8,800 miles so far and played in three quite demanding cities in terms of weather -- Natal, Manaus and Recife -- before they reached knockout stages.

In the same group of travel-and-weather-resilient sides, Mexico traveled over 8,500 miles and played in the similarly hot trio of Natal, Fortaleza and Recife, getting to the round of 16 just like their Northern neighbours. Germany reduced the amount of travel to 5,500 miles by setting their own camp -- designed and built specifically for them -- in the Northeast, but they played in another scary trio of venues -- Salvador, Fortaleza and Recife.

... and defeated by it

Not so successfully, Italy struggled under the sun of Manaus, Recife and Natal after 8,500 miles flown and extenuating heat.

Both manager Cesare Prandelli and centre-back Giorgio Chiellini bitterly complained of the heat and lack of water breaks after the final match -- among other biting issues -- while many could tell the elders in the squad felt the lack of air in their lungs. After their opening win over England, the second halves of matches felt way too long for Italy.

Luck on their side

While some sides had to defeat opposition, travels and weather, others made the most of a fantastic draw, at least in what regards to flights and heat. Belgium, for instance, have travelled just over 1,000 miles and don't know what playing in hot and humid weather means so far.

Lionel Messi and Argentina and pleasant surprise Algeria haven't travelled much, either, and enjoyed nice weather in all of their three matches. Their rested legs should help them in the knockout stages indeed.

Tough luck never ends

Once in the knockout stages, you can probably guess the identities of a couple of teams that will have to play in tough weather: yes, Mexico and the U.S are due to visit the hottest part of Brazil again in their next matches.

The Mexicans' endurance to hot weather will be tested to the extreme, as they not only are due to play a 1 p.m. match in Fortaleza against the Netherlands, but also -- in a case of what would indeed be categorised under a famous victory -- they would play their quarterfinals encounter in Salvador at 5 p.m. The Dutch obviously follow the same path with the same trips in case of victory, but they have not gone under the same demanding group locations as Mexico.

The U.S. face the luckiest -- and probably most fresh -- side from the group stage, Belgium, who will finally be asked to play in demanding weather, in Salvador at a 5 p.m. kickoff. The winner will play in Brasilia, a nicer temperature city, for a place in the semis.

The last couple of teams with a demanding schedule ahead in terms of temperature play will meet in Recife at 5 p.m. on June 29. After a cool first three matches, Greece will face Costa Rica -- more experienced in Brazilian heat following matches in Fortaleza and Recife itself during the first phase. The winning side will have the pleasure of meeting the victor of Netherlands-Mexico in Salvador six days later.

Lucky until the end

Argentina and Algeria can consider themselves unbelievably fortunate. In the event of any of them reaching the final, they would not have to set foot in any of the tough-weather venues in the entire tournament.

When you think that Mexico (five) or the U.S. (four) would have to play most of their World Cup games in their way to the final under strenuous conditions in only three weeks, the physical advantage that Argentinians and Algerians enjoy is quite significant. We'll see if they can make the most of it.